Glutathione Peroxidase Enzyme Activity in Aging

AbstractGlutathione peroxidase (GPx) is a selenocysteine-containing peroxidase enzyme that defends mammalian cells against oxidative stress, but the role of GPx signaling is poorly characterized. Here, we show that GPx type 1 (GPx1) plays a key regulatory role in the apoptosis signaling pathway. The absence of GPx1 augmented TNF-α-induced apoptosis in various RIPK3-negative cancer cells by markedly elevating the level of cytosolic H2O2, which is derived from mitochondria. At the molecular level, the absence of GPx1 led to the strengthened sequential activation of sustained JNK and caspase-8 expression. Two signaling mechanisms are involved in the GPx1-dependent regulation of the apoptosis pathway: (1) GPx1 regulates the level of cytosolic H2O2 that oxidizes the redox protein thioredoxin 1, blocking ASK1 activation, and (2) GPx1 interacts with TRAF2 and interferes with the formation of the active ASK1 complex. Inducible knockdown of GPx1 expression impaired the tumorigenic growth of MDA-MB-231 cells (>70% reduction, P = 0.0034) implanted in mice by promoting apoptosis in vivo. Overall, this study reveals the apoptosis-related signaling function of a GPx family enzyme highly conserved in aerobic organisms.

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Evaluation of Superoxide Dismutase and Glutathione Peroxidase Enzyme Polymorphisms in Familial Mediterranean Fever Patients

Electronic Journal of General Medicine ◽

10.15197/ejgm.01463 ◽

2015 ◽

Vol 12 (4) ◽

Author(s):

Ali Akbas ◽

Hüseyin Ozyurt ◽

Semsettin Sahin ◽

Ismail Benli ◽

Oguzhan Saylan ◽

...

Keyword(s):

Superoxide Dismutase ◽

Familial Mediterranean Fever ◽

Glutathione Peroxidase ◽

Enzyme Polymorphisms ◽

Peroxidase Enzyme ◽

Mediterranean Fever

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Вплив хлориду кадмію на стан антиоксидантної системи у печінці щурів

Вісник Полтавської державної аграрної академії ◽

10.31210/visnyk2013.02.28 ◽

2013 ◽

pp. 102-103

Author(s):

Б. В. Гутий

Keyword(s):

Lipid Peroxidation ◽

Superoxide Dismutase ◽

Enzyme Activity ◽

Glutathione Peroxidase ◽

Antioxidant System ◽

Cadmium Chloride

Розкрито особливості антиоксидантної системиорганізму щурів за хронічного кадмієвого токсикозу.Встановлено, що хлорид кадмію у токсичній дозісприяє зниженню активності ферментної й нефер-ментної системи антиоксидантного захисту, на щовказує зниження ферментів глутатіонпероксидази,глутатіонредуктази, супероксиддисмутази, катала-зи та відновленого глутатіону у печінці щурів. Ре-зультати досліджень вказують на те, що хронічнийкадмієвий токсикоз призводить до посиленої акти-вації процесів ліпопероксидації. The features of the antioxidant system of rats with chronic cadmium toxicosiare disclosed. It wasresearched that cadmium chloride in toxic doses reduces enzyme activity of antioxidant system, asindicated by the decrease in enzyme glutathione peroxidase, hlutationreduktazy, superoxide dismutase,catalase and restored glutathione in the liver and blood of rats. The results indicate that chroniccadmium toxicosis leads to enhanced activation of lipid peroxidation.

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Selenium-dependent glutathione peroxidase protein and activity: immunological investigations on cellular and plasma enzymes

Blood ◽

10.1182/blood.v68.3.640.bloodjournal683640 ◽

1986 ◽

Vol 68 (3) ◽

pp. 640-645 ◽

Cited By ~ 1

Author(s):

K Takahashi ◽

HJ Cohen

Keyword(s):

Enzyme Activity ◽

Glutathione Peroxidase ◽

Protein Content ◽

Polyclonal Antibodies ◽

Plasma Enzyme ◽

Plasma Enzymes ◽

Erythrocyte Enzyme ◽

Dependent Protein ◽

Gshpx Activity ◽

Almost All

Selenium-deficient humans and animals are known to be deficient in glutathione peroxidase (GSHPx) activity in their cells and plasma. To determine the relationship between enzyme activity and protein content, the enzyme was purified from human erythrocytes, and polyclonal antibodies were made against the purified protein in rabbits. These antibodies were found to be monospecific, noninhibitory, and capable of precipitating the enzymatic activity. All the GSHPx activity in erythrocytes and almost all the activity in neutrophils and platelets was precipitated by these antibodies. None of the plasma enzyme was precipitated by these antibodies, indicating that the plasma enzyme activity was attributable to a different selenium dependent protein moiety. Utilizing a radioimmunoassay, we were able to determine that there was a direct relationship between GSHPx activity and protein content in the erythrocytes of both normal and selenium-deficient individuals, and a similar relationship between control and selenium- deficient rat erythrocytes and liver cells. Thus, the ability to examine GSHPx as a protein resulted in two new observations concerning the selenium-dependent GSHPx. The first is that the plasma enzyme is antigenically distinct from the erythrocyte enzyme, and the second is that in the absence of selenium, there is a concomitant decrease in GSHPx protein.

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Effect of moisture stress on leaf protein, proline, peroxidise activity and yield in released and pre-released genotypes of groundnut (Arachis hypogaea L.)

INTERNATIONAL JOURNAL OF AGRICULTURAL SCIENCES ◽

10.15740/has/ijas/16.2/260-264 ◽

2020 ◽

Vol 16 (2) ◽

pp. 260-264

Author(s):

H.Y. Patil ◽

Pooja ◽

V.P. Chimmad

Keyword(s):

Enzyme Activity ◽

Co2 Concentration ◽

Moisture Stress ◽

Leaf Protein ◽

Growth Stages ◽

Arachis Hypogaea L ◽

Moisture Deficit ◽

Peroxidase Enzyme ◽

Rain Fall ◽

The Impact

The performance of crops need to be assessed for their production under erratic rain fall pattern, increased temperatures, and enhanced atmospheric CO2 concentration. In the present study groundnut was chosen as test crop and selected genotypes [four released (GPBD-4, G2-52, Dh-86 and TMV-2) and four pre-released (Dh-245, Dh-232, Dh-256 and Dh-257)] were studied to quantify the impact of moisture deficit stress at critical growth stages i.e., 40 to 80 DAS and 80 DAS to harvest. Leaf protein and proline increases in tolerant genotypes at higher moisture stress levels than susceptible genotypes as they acts as osmolytes and maintains the turgidity of the cell and hence, checks the water loss and peroxidase enzyme activity which in turn scavenges ROS produced due to stress as a result there was reduction in yield. The genotypes, GPBD-4, Dh-257 and Dh-256 recorded higher per cent increase in leaf soluble protein, leaf proline and peroxidase enzyme activity at all the stages. Increase was higher at 80 DAS to harvest stressed plants than 40 to 80 DAS stressed plants.

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